The current paradigm for military armor development goes roughly in the following steps. A requirement that defines ballistic-performance and coverage-area is established based on current needs in the field. The requirement comes back to the military hardware design community, and a carrier-garment and a ballistic-package are designed to fulfill the requirement. At this point interactions with other armor components and load carriage are resolved as best as can be arranged. If the garment solution gets through a wear trial process, then the garment and the ballistic-package can be fielded.
However, in the meantime the situation in the field has evolved. The original operational needs that established the basis for the armor requirement have now changed, and the field wants a new combination of ballistic protection and coverage-area.
This is a dilemma. Conflicts and tactics evolve too quickly for the armor development community to keep up with operational changes.
In addition, body armor requirements can change from mission to mission. An armor system that is acceptable for one mission, might be unacceptable for another. If an armor system is not suitable for a given mission, a soldier is faced with the choice of endangering his or her life by wearing the armor and thereby reducing his or her ability to perform the mission effectively, or endangering his or her life by not wearing the armor at all, and thereby being more vulnerable to enemy ballistic threats.
What is clearly needed, therefore, is a protective armor system that is field-adaptable to varying missions and threats. This implies an armor system that is modular, whereby various portions of the armor can be exchanged or simply removed so as to adjust the protection level, weight, thermal burden, and flexibility according to the immediate needs of each conflict and each mission. However, the creation of a practical, modular, field-adaptable armor system has proven difficult to achieve, especially for dismounted soldiers, for whom it is highly critical to limit weight and thermal burden, and to maintain maximum flexibility and mobility.
The task of designing modular, field-adaptable armor is even more difficult when protection of the extremities is required. For example, Improvised Explosive Devices (IEDs) are tactical and strategic insurgent weapons which exact a tremendous toll on warfighters. Unlike heads and torsos, dismounted warfighter arms and legs are typically not armored, and are therefore are vulnerable to a complex range of blast trauma injuries (debris, Packed Metal Projectiles, fragments, overpressure, burns, and acceleration-related joint/tissue damage) which result in significant morbidity and mortality. A lightweight, flexible extremity protection for IEDs and other fragmentation munitions suitable for use by a dismounted soldier has not existed.
Currently, there are add-on components for shoulder and side protection which augment the basic vest area protection of bodyarmor. While not strictly extremities, they represent an effort to increase the area of protective coverage. However, these solutions have not been extended to full extremity protection due to the concerns noted above.
An extremity protection solution called the QuadGuard System® (Applicant makes no claim to the trademark) was developed for Humvee turret gunners. This system weighs approximately 0.85 lbs/ft2 (122 oz/yd2). Another turret gunner blast protection strategy called the Cupola Protective Ensemble was adopted by modification of the Explosive Ordinance Disposal (EOD) counter-mine suit. For these vehicle-mounted applications, an active cooling vest fed from an on-vehicle chiller can be provided so as to avoid heat-stress.
However, while these systems are suitable for use by a mounted turret gunner, who does not require mobility beyond seated operation of the turret gun, none of these solutions is a viable candidate for dismounted infantry, due to their mass and/or thermal burden.
The carry loads for modern infantry and tactical operations are so high that additional extremity protection is only used in a very limited set of circumstances. In addition, the currently available extremity gear can only be used for approximately 30 minutes, because the thermal burden is so high that core body temperatures begin to exceed safe levels after this time. In general, the current approach to extremity protection is to model the extremity protective panels after the fabric panels found in the ballistic vest. This approach leads to a weight of 0.5-1 lb/ft2 (72-144 oz/yd2). Panels of this type do not permit heat transfer and produce a Total Heat Loss result of less than 150 watts/m2 of covered area. Experience has shown that this low rate of heat loss has a strong tendency to cause heat stress.
The task of designing modular, field-adaptable armor is made even more difficult by the conventional wisdom in the art that requires protection only in the central region of a panel. The issue comes from the interpretation of effective or TESTED area density. In existing test methods, generally the “Fair-Shot” placement excludes a 2″ border around the edge of a tested panel. For a 10 inch by 12 inch panel, this leaves only 40% of the area in the Fair-Shot zone, and the problem gets worse as the panel sizes get smaller.
This is one reason why exiting armor systems typically include only a few large panels, and it is yet another reason why extremity armor solutions are so difficult to design, due to the very small sizes of the required panels. Flexible, fabric-based “soft” panels in particular tend to degrade and unravel over time near their edges, and would require significant overlap of modules if included in a modular armor system. Ceramic and metal panels, on the other hand, can perform well near their edges. However, they are cumbersome to join without a gap in protection, and the rigidity of such panels prevents them from being joined in a fixed relationship, because the result of such an approach would be a rigid garment that would be unacceptable to a mobile, dismounted infantry soldier. A garment constructed from rigid modules that included extremity protection would also be very heavy, and would be nearly impossible for a soldier to put on or to take off without assistance due to its weight and rigidity.
A body armor system is therefore needed which provides continuous protection for extremities as well as for the torso and head, and which is modular, field-adaptable, flexible, lightweight, and breathable, thereby meeting the needs of dismounted infantry soldiers in evolving combat environments.